| 摘要 |
<p>A hypodermic syringe employs a piston in a cylinder having an injection needle at one end and a handle at the other end from which the piston rod is actuated. Actuation is by displacement of a movable element, e.g. a trigger coupled by reduction gearing to the piston rod. The handle is moulded, pref. in plastic, with an integrally mouled side fin serving as a grip for the user's thumb. The hand pref. has two symmetrical fins, one on each side to suit right and left handed users. The fin permits the handle to be gripped between thumb on the fin and index finger in front on the handle, the remaining fingers being free to combine in operating a trigger. The reduction gearing pref. comprises a spring-loaded, pivoted lever of which one end forms a trigger and the other end is linked to a pawl which engages a rack fixed to the back end of the piston rod. Provides a manually operated hypodermic syringe partic for injecting local anaesthetics. The handle can be gripped securely and comfortably for long periods without fatigue. This permits injections to be made under constant control of delivery rate.</p> |
